Butterfly air control valve



FIG. 1 is a perspective view of the manifold assembly in accordance with the invention;

FIG. 2 is a plan view of the manifold assembly of FIG. 1;

FIG. 3 is a side view of the manifold assembly of FIG. 1; and,

FIG. 4 is a cross-sectional view through section 4--4 of FIG. 2. 

The ornamental design for a butterfly air control valve, as shown and described. 